A known conventional terminal-to-terminal communication system is that communications are performed by relaying some terminals among the terminals far beyond a radio wave reachable range as well as between terminals within a radio wave reachable range across a multi-hop wireless communication network. In an environment where a route between the terminals in the multi-hop wireless communication network changes (switchover) at a high frequency, a link state routing system is exemplified as a route recognizing system suited to a case of performing the communications with a high throughput between two pieces of specified terminals.
In a multi-hop wireless communication network system, there is proposed a system (Guangyu Pei et al, “Fisheye State Routing: A Routing Scheme for Ad Hoc Wireless Networks”, ICC2000) in which the principle of the link state routing system (J. Moy, “OSPF Version 2”, RFC1247 July 1991.) employed for a wired network is applied to a wireless network substantially as it is. An evaluation about the wireless communication system is conducted based on the assumption mainly of 2.4 GHz band 2 Mbps IEEE802.11b Wireless LAN (Local Area Network).
At the present time, however, it is general to perform high-throughput packet communications utilizing a wireless LAN exhibiting a much higher transmission speed on the order of 11 Mbps, and, at a research-and-development stage, a development of a wireless LAN having 54 Mbps at the maximum is underway. The wireless communication system has such a property that a radio wave reachable distance becomes shorter as the transmission speed gets higher, and hence, when the two terminals located at the same distance away from each other try to perform multi-hop communications by utilizing a higher speed wireless communication system, a greater number of relay terminals (hop terminals) than in the evaluation result in the literature are required.
In the conventional system, when the two terminals perform the packet communications by way of the multi-hop wireless communications, a data size of control packets transmitted by the single terminal in order to announce a neighboring terminal list increases in proportion to a total number of the terminals participating in the packet communications (a total number of the transmission terminals, the receipt terminals and the relay terminals). Accordingly, as the number of the relay terminals rises, the control packets give a large overhead to bandwidth of wireless links, resulting in such a problem that the throughput of the data packets is restricted.